Cadmium/Calcium and stable isotope ratios of benthic foraminifera from the northeast Atlantic Ocean

The delta13C and Cd measurements from benthic foraminifera from Biogeochemical Ocean Flux Study (BOFS) northeast Atlantic Ocean sediment cores are presented. The delta13C values in glacial foraminifera are consistent with those from elsewhere in the North Atlantic Ocean. For intermediate water (1000 - 2000 m water depth), delta13C values were higher at the last glacial maximum than in present North Atlantic Deep Water (NADW), whereas for deep water (>2000 m) they were lower during the glacial maximum. The Cd concentrations of glacial northeast Atlantic intermediate water were lower than those of present NADW. However, deepwater Cd concentrations increased to values between NADW and present Pacific Deep Water (PDW). The delta13C and Cd data are consistent and show that the northeast Atlantic Ocean was strongly stratified with 13C enriched, low Cd intermediate water overlying 13C depleted, high Cd deep water. […]

本描述展示了来自生物地球化学海洋通量研究（BOFS）东北大西洋海洋沉积岩心的底栖有孔虫的碳同位素δ13C和镉（Cd）含量测量数据。冰川期有孔虫的δ13C值与北太平洋其他地区的值一致。在过渡水域（1000-2000米水深），δ13C值在最后一个冰川最大期高于现今的北太平洋深层水（NADW），而对于深水（>2000米）而言，在冰川最大期则低于此值。冰川期东北大西洋过渡水域的镉浓度低于现今的北太平洋深层水。然而，深水镉浓度上升至介于NADW与现今太平洋深层水（PDW）之间的值。δ13C和镉数据的一致性表明，东北大西洋海洋在13C富集、镉含量低的过渡水域之上存在13C贫乏、镉含量高的深层水，表明其具有强烈的层状结构。